Discrimination of capillary and arterio-venular blood flow in skin by laser Doppler flowmetry.
Med Biol Eng Comput
; 29(4): 387-92, 1991 Jul.
Article
em En
| MEDLINE
| ID: mdl-1787754
ABSTRACT
The scattering and absorption of light by tissue and blood is wavelength dependent; the tissue penetration of green light (lambda = 543.5 nm) is about 60 per cent of that of red light (lambda = 632.8 nm) but the absorption of green light by blood is about 20 times greater than for red light. The effect of this difference has been studied by observing the responses of skin blood flow to heat and weal, measured by laser Doppler flowmetry at the two wavelengths. By using time autocorrelation function analysis (ACF) of the scattered light measured, low and high frequency components have been associated with capillary and larger vessel flow, respectively. The comparison of ACF from scattered green and red light has shown that measurements cannot be interpreted by only considering light penetration depth through a homogeneous tissue. Light absorption and multiple scattering by blood at the individual microvessel level, blood rheology and vessel morphology are parameters which are considered for greater attention.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Pele
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
Med Biol Eng Comput
Ano de publicação:
1991
Tipo de documento:
Article